Cloudtrail Regional

Category: CLOUD · Difficulty: Advanced · Points: 500 · Challenge: 536

Background

Adversaries operated within an under-monitored secondary cloud region. Parse multi-region CloudTrail audit logs to identify anomalous API calls and carved secrets. FORMAT: FLAG{ }

Analysis

The published dataset is 9666 bytes of structured telemetry. It carries no live credentials and describes an environment rather than granting access to one, so none of the interactive steps named in the brief could be performed. One field holds a base64 segment rather than readable text. Decoding that segment is the whole of the extraction:

$ grep -o '[A-Za-z0-9+/]\{20,\}' cloud_audit-094.json | while read -r s; do \
    printf '%s' "$s" | base64 -d 2>/dev/null; echo; done
RkxBR3tjd2EyMDI2X2YyNGQ0MjcwYTEyNGMwN2N9
FLAG{cwa2026_f24d4270a124c07c}

The recovered value was accepted for this challenge.

Result

FLAG{cwa2026_f24d4270a124c07c}